The majority of Telltale's games do have discs for the PC versions of their games. If that isn't what you want, then Sam and Max season 1 and season 2 both had separate disc releases for the Wii I believe.

Don't bother with the Wii disc versions, they're really not very good. BTTF especially, which suffers from some terrible framerate drops. Sam & Max Series One frequently had the end of sentences cut off and the driving sections had a framerate equivalent to a slideshow presentation. Series Two... I never really tried, but I've not heard great things either.

The majority of the PC versions have all had disc versions (The Puzzle Agent games, the two Poker games and Hector are the exceptions), but as far as I'm aware only the more recent console games have had / are getting disc versions. BTTF onward, IIRC.

PS3? I've only seen disc releases for Back to the Future. I don't know if any of the other games will be released in a similar manner, but I'd be surprised if The Walking Dead didn't get one, considering it's Telltale's most successful game to date. Don't expect previous games to get one though.